New research suggests that taking medicine for ear infections might be related to a reckless appetite. Antibiotics have done wonders for extending human life by killing off deadly pathogens. But they target "a particular disease the way a nuclear bomb targets a criminal, causing much collateral damage," says Karen Kaplan in the Los Angeles Times. Incidental victims include a whole host of microbes that actually help us, and "our friendly flora never fully recover," argues New York University microbiologist Martin Blaser in the journal Nature. The unintended targets of antibiotics might also include our waistlines, according to new theories linking the drugs to a sharp rise in obesity. Here's what you need to know: